14
6.1 Faults and fixes
If problems arise when the product is in use,
check for possible faults and fixes in the table.
If you are unsure what is wrong, contact the
6. TROUBLESHOOTING
TROUBLESHOOTING
Problem
Possible cause of fault
Possible solution
There is leakage/dripping
from the safety valve/
there is often water on
the floor by the cylinder
in the morning
Pressure reduction valve, water meter
or blocked non-return valve on the
water intake.
Water pressure into the system is too
high.
Fit AX expansion vessel which absorbs ex-
pansion during heating, and fit pressure
reduction valve for stable water pressure
inside the system. The pressure reduction
valve is adjusted in according to the pres-
sure in the expansion vessel. Contact auth.
installer.
The safety valve is worn or there are
particles stuck between the mem-
brane and the valve seat because the
water is dirty
Try to flush with water through the safety
valve. Open valve for approx. 1 minute. See
section 5.2. If the valve still leaks, it must be
replaced. Contact auth. installer.
Leak from heating element.
Verify as follows: a) cut the electric sup-
ply, b) unscrew the cover, c) visually check
whether there is a leak from the heating
element. If so, replace the gasket/heating
element. Contact auth. installer.
No hot water
Power supply interrupted.
Verify that the fuse is on / the plug is
plugged in to the wall contact / the earth
breaker has not tripped.
Thermostat has cut out.
Press the ‘RESET’ button on the safety
thermostat; see ‘User guide’.
Heating element is defective.
Replace heating element. Contact auth.
installer.
Leak in hot water pipe
Verify as follows: a) close the water supply,
b) wait 2-3 hours, c) feel the tank to see
whether it is hot. If so, there is a leak in
the hot water pipe or elsewhere. Contact
auth. installer.
Not enough hot water
High consumption in the system.
Switch to a larger OSO water heater. Con-
tact auth. installer.
Not high enough tem-
perature
The thermostat is set for low tempera-
tures.
Check the thermostat settings. Turn up to
75°C; see ‘User guide’.
Change from cold to hot water in taps. Contact auth. installer.
Fuse/earth breaker trips
repeatedly
Possible fault in the heater’s electrical
system.
Verify as follows: a) cut the electric supply,
b) unscrew the cover, c) visually check the
junction box for any problems. If so, con-
tact auth. installer to check. Fit the cover.
Long time before the
water reaches the tap
Long stretch of pipe from water
heater to tap.
Fit circulation wire or heating cable to HW
pipe. Or fit an auxiliary heater by the tap.
Contact auth. installer.
Knocking in the pipes
when the hot tap is closed
Large pressure increase when the tap
is closed quickly.
Completely normal. Fit AX expansion ves-
sel if troublesome. Contact auth. installer.
installer (see product type plate) or OSO Hot-
water AS - see section 7.1.
